The present invention relates generally to inflatable seats and, more particularly, to an inflatable seat for a bicycle or other application wherein there is a need to adjust the contour and support of the seat to suit the individual requirements of the user.
It is well known that one can experience considerable discomfort when using a seat for a substantial length of time. To some extent, this seat-related discomfort is due to inadequate or improper support of the buttocks and legs. In addition, because the contours of most seats generally are not adjustable, the user is unable to modify the seat to conform to his or her unique physical characteristics and personal preferences. Similarly, the user is unable to eliminate uncomfortable pressure points as they develop during use. These limitations give rise to substantial seat-related discomfort, particularly for those people who must remain seated for extended periods without recess, such as office workers, vehicle operators, and wheelchair users.
Seat-related discomfort can be exacerbated in a vehicle, such as a car, motorcycle, or tractor, due to the jarring and vibrations associated with the motion of the vehicle over the roadway surface or terrain. In particular cases, vibrations and jarring have been known to cause injury to the user. To some extent, these concerns are addressed by the use of shock absorbers or vibration dampening systems. However, some vehicles contain only limited vibration dampening capability. Thus, the users of such vehicles will experience more acute discomfort and a higher likelihood of seat-related injury. In vehicles that are manufactured with rigid frames, such as bicycles or wheelchairs, these effects will be even more pronounced.
The problems discussed above are particularly acute in vehicles, such as bicycles, exercise cycles, and the like, which are equipped with seats designed to facilitate the movement of a rider's legs in pedalling. Seats in these types of vehicles are generally smaller in size and more rigid than conventional seats. Consequently, the seat provides even less cushioning and support for the buttocks and legs of the user.
In the past, seat-related discomfort has been addressed by providing seats with additional padding, internal springs, or external cushions in order to provide a softer, more flexible surface. Additionally, seats have been outfitted with inflatable pads or cushions which could be adjusted to the user's preferred level of inflation. These inflatable seats and seat cushions aided in the reduction of vibrations and jarring associated with bicycle travel. Typically, such devices were composed of bags or tubes equipped with a valve so that a given tube could be connected to an air source and inflated, thereby altering the pressure of the tube and hence the resilience of the seating surface. Some of these designs could be inflated with a liquid in order to provide added resiliency.
Despite the improvements afforded, these inflatable seat designs are subject to a number of serious limitations. One such limitation is that the contour and support characteristics of these seats are inadequate and subject to variation. For example, when these seats are in use, the air flows away from the point of greatest pressure causing the inflatable tubes or bags to lose their shape. Further, a change in the user's position is accompanied by a corresponding change in distribution of air within the tube or bag. As a result, the user is subjected to shifting and sagging of the inflatable seat or cushion. Some designs attempted to remedy these deficiencies by including webbing within the tubes or bags. Nevertheless, such modifications have met with only limited success. In designs where individual tubes are connected in fluid communication with one another, air can flow out of the tube or bag subjected to the greatest amount of pressure and where the need for support is the greatest. As a result, these designs are subject to additional instability.
Moreover, existing inflatable seats have a limited range and variety of adjustments. Consequently, such seats cannot be adjusted to the precise contours and idiosyncracies of the anatomy or personal preferences of the individual user. Similarly, the user is unable to remove specific pressure points as they develop during extended use.
The application of these designs further is limited because they cannot be easily and economically altered or customized in an effort to adapt the seat to meet each individual's demands. Similarly, many of the seat cushion designs cannot be modified for production as part of the seat itself, nor can they be adapted for use in a seat cushion or seat cover. In other designs, such alterations can only be accomplished with considerable effort and expense.
The means employed to inflate and control inflatable seats also have limited application. In many designs, the level of inflation cannot be adjusted while the user is positioned on the seat. Consequently, the user must experiment by trial and error to achieve the proper seat inflation. In other designs, the seat can be adjusted while the seat is in use, but the means provided is awkward or inconvenient to use. Moreover, these control and adjustment mechanisms are often too expensive or bulky for certain applications.
In addition to these general considerations, it should be noted that pedal-operated vehicles have several seat-related considerations which have no counterpart in other types of seats. First, since the rider's legs must be able to move freely in order to facilitate pedalling, the rider's weight will concentrated primarily on the saddle portion of the seat. Consequently, the rider will experience considerable pressure on the perineum, the end of the spine, and the pelvic bones. In addition, the motion of the rider's legs and body gives rise to forces which are not present in the use of other types of seats. In pedal-operated devices, a substantial component of force is exerted in a direction normal to the seat surface. Consequently, the level of discomfort experienced by the rider is substantially greater than with a conventional seat. Further, in the extremes of the pedalling motion, as the rider's weight is shifted from one side to the other, the air or fluid in the inflatable pad is forced away from the points of greatest pressure and the pad tends to collapse and distort. As a result, the rider experiences a shifting or sagging of the seat's cushioning and support with each pedalling motion. The repeated nature of this effect is an independent source of discomfort for the rider.
Not surprisingly, many attempts have been made to provide these pedal-operated devices with inflatable seats or inflatable seat covers in order to alleviate the distinctive discomfort associated with their use. Due to the unique functional demands, however, these attempts have met with only limited success. Like their conventional seat counterparts, the contour and support characteristics of these seat designs are subject to variation. The extent and frequency of these variations, moreover, are magnified by the repeated motion of the rider and the substantial forces generated when pedalling.
From the foregoing, it will be appreciated that there is a need for an inflatable seat or cover therefor having contour and support characteristics that are adjustable over a wide range, yet one that provides firm and stable support for the user, particularly but not exclusively for pedal-operated devices such as bicycles. There is a further need for an inflatable seat or cover that can be combined with an inexpensive and lightweight fluid source and controller such that the contour and support characteristics can be selectively adjusted while the seat is in use. The present invention fulfills these and other needs.